U.S. patent application number 16/237723 was filed with the patent office on 2019-07-11 for devices, systems, and methdos for epicardial cardiac monitoring.
This patent application is currently assigned to CVDevices, LLC. The applicant listed for this patent is CVDevices, LLC. Invention is credited to Ghassan S. Kassab, Jose A. Navia, SR..
Application Number | 20190209010 16/237723 |
Document ID | / |
Family ID | 39645058 |
Filed Date | 2019-07-11 |
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United States Patent
Application |
20190209010 |
Kind Code |
A1 |
Kassab; Ghassan S. ; et
al. |
July 11, 2019 |
DEVICES, SYSTEMS, AND METHDOS FOR EPICARDIAL CARDIAC MONITORING
Abstract
Devices, systems, and methods for remotely monitoring
physiologic cardiovascular data are disclosed. At least some of the
embodiments disclosed herein provide access to the external surface
of the heart through the pericardial space for the delivery of the
sensor to the epicardial surface of the heart. In addition, various
disclosed embodiments provide for a memory device capable of
receiving the physiologic cardiovascular data collected by the
sensors and transmitting such data wirelessly to a remote
location.
Inventors: |
Kassab; Ghassan S.; (La
Jolla, CA) ; Navia, SR.; Jose A.; (Buenos Aires,
AR) |
|
Applicant: |
Name |
City |
State |
Country |
Type |
CVDevices, LLC |
San Diego |
CA |
US |
|
|
Assignee: |
CVDevices, LLC
San Diego
CA
|
Family ID: |
39645058 |
Appl. No.: |
16/237723 |
Filed: |
January 1, 2019 |
Related U.S. Patent Documents
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Application
Number |
Filing Date |
Patent Number |
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15854272 |
Dec 26, 2017 |
10165947 |
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16237723 |
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14225145 |
Mar 25, 2014 |
9848777 |
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15854272 |
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12522279 |
Nov 9, 2009 |
8682411 |
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PCT/US2008/000796 |
Jan 22, 2008 |
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14225145 |
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60817421 |
Jun 30, 2006 |
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Current U.S.
Class: |
1/1 |
Current CPC
Class: |
A61B 5/0031 20130101;
A61B 2560/066 20130101; A61B 5/1107 20130101; A61B 5/6852 20130101;
A61B 5/046 20130101; A61B 5/6869 20130101; A61B 5/0422 20130101;
A61B 5/6882 20130101; A61B 5/688 20130101; A61B 5/0215 20130101;
A61B 5/024 20130101 |
International
Class: |
A61B 5/00 20060101
A61B005/00; A61B 5/042 20060101 A61B005/042; A61B 5/11 20060101
A61B005/11; A61B 5/0215 20060101 A61B005/0215 |
Claims
1. A sensor assembly for collecting physiologic data from a
targeted tissue, the sensor assembly comprising: a scaffold
assembly having a body comprising a bottom portion and having a
first delivery channel therethrough, the bottom portion having a
plurality of openings therein which are in fluid communication with
the first delivery channel; a delivery catheter having first and
second lumens extending therethrough, the first lumen comprising a
second delivery channel in fluid communication with the first
delivery channel of the scaffold assembly, and the second lumen
having a wire channel in communication with the bottom portion of
the scaffold assembly; and at least one sensor capable of
collecting physiologic data from a targeted tissue, the at least
one sensor coupled within the body of the scaffold assembly; and
wherein a connecting wire for transferring physiologic data
collected by the at least one sensor can be at least partially
positioned within the wire channel configured to receive the
connecting wire; and wherein the first delivery channel of the
scaffold assembly, the second delivery channel of the delivery
catheter, and the number of openings in the bottom portion of the
scaffold assembly are capable of allowing an adhesive substance to
flow therethrough and onto the targeted tissue.
2. The sensor assembly of claim 1, wherein the scaffold assembly is
comprised of a flexible material.
3. The sensor assembly of claim 2, wherein the scaffold assembly is
capable of shifting between a first folded position comprising a
first perimeter dimension and a second open position comprising a
second perimeter dimension, wherein the first perimeter dimension
is smaller than the second perimeter dimension.
4. The sensor assembly of claim 1, wherein the body of the scaffold
assembly further comprises a plurality of magnetic beads embedded
therein.
5. The sensor assembly of claim 1, wherein the body of the scaffold
assembly surrounds a periphery of the at least one sensor.
6. The sensor assembly of claim 1, wherein the targeted tissue
comprises an epicardial surface of a heart.
7. A method for attaching a sensor assembly to a surface of a
targeted tissue comprising the steps of: providing a sensor
assembly comprising: a scaffold assembly having a body comprising a
bottom portion and having a first delivery channel therethrough,
the bottom portion having a plurality of openings therein which are
in fluid communication with the first delivery channel, a delivery
catheter having first and second lumens extending therethrough, the
first lumen comprising a second delivery channel in fluid
communication with the first delivery channel of the scaffold
assembly, and the second lumen having a wire channel in
communication with the bottom portion of the scaffold assembly, and
at least one sensor capable of collecting physiologic data from a
targeted tissue, the at least one sensor coupled within the body of
the scaffold assembly, wherein a connecting wire for transferring
physiologic data collected by the at least one sensor can be at
least partially positioned within the wire channel configured to
receive the connecting wire, and wherein the first delivery channel
of the scaffold assembly, the second delivery channel of the
delivery catheter, and the number of openings in the bottom portion
of the scaffold assembly are capable of allowing an adhesive
substance to flow therethrough and onto the targeted tissue;
positioning the at least one sensor of the sensor assembly on a
targeted tissue surface; inserting the adhesive substance into the
second delivery channel of the delivery catheter; applying the
adhesive substance to the targeted tissue surface by advancing the
adhesive substance through the second delivery channel of the
delivery catheter, the first delivery channel of the scaffold
assembly, and through the plurality of openings in the bottom
portion of the scaffold assembly; and allowing the adhesive
substance to adhere to the targeted tissue surface and the bottom
portion of the scaffold assembly.
8. The method of claim 7, wherein the adhesive substance is
selected from the group consisting of a ferromagnetic adhesive, a
biological adhesive, and a nonbiological adhesive.
9. The method of claim 7, wherein the scaffold assembly is
comprised of a flexible material and is capable of shifting between
a first folded position comprising a first perimeter dimension and
a second open position comprising a second perimeter dimension,
wherein the first perimeter dimension is smaller than the second
perimeter dimension, and wherein the step of positioning the at
least one sensor of the sensor assembly on a targeted tissue
surface further comprises the steps of: shifting the scaffold
assembly of the sensor assembly into the first folded position;
inserting the sensor assembly into a catheter comprising a proximal
end and a distal end; and delivering the distal end of the catheter
containing the sensor assembly via catheterization and percutaneous
methods to the targeted tissue.
10. The method of claim 9, further comprising the steps of:
advancing the sensor assembly through the distal end of the
catheter; shifting the scaffold assembly of the sensor assembly
into the second open position; and positioning the at least one
sensor of the sensor assembly on the targeted tissue surface.
11. The method of claim 10, further comprising the step of:
withdrawing the catheter.
12. The sensor assembly of claim 1, wherein the at least one sensor
is configured for placement on a surface of the targeted
tissue.
13. The sensor assembly of claim 1, wherein when the adhesive
substance is inserted into the second delivery channel, the
adhesive substance can advance from the second delivery channel to
the first delivery channel and through the plurality of openings in
the bottom portion of the scaffold assembly.
14. The sensor assembly of claim 1, wherein the first delivery
channel and the second delivery channel are configured to deliver
the adhesive substance therethrough.
15. A method for attaching a sensor assembly to a surface of a
targeted tissue comprising the steps of: positioning the at least
one sensor of the sensor assembly of claim 1 on the surface of the
targeted tissue.
16. The method of claim 15, further comprising the step of:
inserting the adhesive substance into the second delivery channel
of the delivery catheter.
17. The method of claim 16, further comprising the step of:
applying the adhesive substance to the targeted tissue surface by
advancing the adhesive substance through the second delivery
channel of the delivery catheter, the first delivery channel of the
scaffold assembly, and through the plurality of openings in the
bottom portion of the scaffold assembly; and
18. The method of claim 17, further comprising the step of:
allowing the adhesive substance to adhere to the targeted tissue
surface and the bottom portion of the scaffold assembly.
Description
PRIORITY
[0001] The present application is related to, claims the priority
benefit of, and is a U.S. continuation patent application of, U.S.
patent application Ser. No. 15/854,272, filed Dec. 26, 2017 and
issued as U.S. Pat. No. 10,165,947 on Jan. 1, 2019, which is
related to, claims the priority benefit of, and is a U.S.
continuation patent application of, U.S. patent application Ser.
No. 14/225,145, filed Mar. 25, 2014 and issued as U.S. Pat. No.
9,848,777 on Dec. 26, 2017, which is related to, claims the
priority benefit of, and is a U.S. continuation patent application
of, U.S. patent application Ser. No. 12/522,279, filed Nov. 9, 2009
and issued as U.S. Pat. No. 8,682,411 on Mar. 25, 2014, which is
related to, and claims the priority benefit of, International
Patent Application Serial No. PCT/US2008/000796, filed Jan. 22,
2008, which is related to, and claims the priority benefit of, U.S.
Provisional Patent Application Ser. No. 60/881,471, filed Jan. 22,
2007. The contents of each of these applications and patents are
hereby incorporated by reference in their entirety into this
disclosure
BACKGROUND
[0002] A healthy cardiac rhythm not only consists of a heart that
beats at the proper pace, but the muscular contractions of the four
chambers of the heart must also be properly mediated such that they
can contract in a coordinated fashion. The heart has specialized
conduction pathways in both the atria and the ventricles that
enable the rapid conduction of excitation (i.e. depolarization)
throughout the myocardium. Normally, the sinoatrial node ("SA
node") initiates each heart-beat cycle by depolarizing so as to
generate an action potential. This action potential propagates
relatively quickly through the atria, which react by contracting,
and then relatively slowly through the atrio-ventricular node ("AV
node"). From the AV node, activation propagates rapidly through the
His-Purkinje system to the ventricles, which also react by
contracting. This natural propagation synchronizes the contractions
of the muscle fibers of each chamber and synchronizes the
contraction of each atrium or ventricle with the contralateral
atrium or ventricle.
[0003] The rate at which the SA node depolarizes determines the
rate at which the atria and ventricles contract and thus controls
the heart rate. The pace at which the SA node depolarizes is
regulated by the autonomic nervous system which can alter the heart
rate so that the heart, for instance, beats at a faster rate during
exercise and beats at a slower rate during rest. The
above-described cycle of events holds true for a healthy heart and
is termed normal sinus rhythm.
[0004] The heart, however, may have a disorder or disease that
results in abnormal activation preempting sinus rhythm, and
resulting in an irregular heartbeat, i.e. an arrhythmia.
Individuals with cardiac ailments, and especially those at risk of
sudden cardiac death ("SCD"), may suffer from an irregular pace
and/or uncoordinated mechanical activity wherein the myocardial
depolarization and contraction of the chambers do not occur
simultaneously. Without the synchronization afforded by the
normally functioning specialized conduction pathways or the proper
pacing by the SA node, the heart's pumping efficiency is greatly
diminished and can thus compromise a patient's cardiac output.
Several different factors may lead to the development of an
arrhythmia, including atherosclerosis, thrombosis, defects in
electrogenesis and nerve impulse propagation, influences of the
sympathetic and parasympathetic systems, ischemia (inadequate
oxygen supply to the cells due to lack of blood flow), and/or poor
vascular control.
[0005] Despite advances in techniques of resuscitation, cardiac
arrest and related cardiac disorders such as those mentioned above
are associated with significant rates of morbidity and mortality.
Due to the increasing incidence of SCD, chronic heart failure, and
other life threatening cardiac ailments, cardiac dysfunction
remains a major public health problem, especially in developed
countries. For example, it is estimated that between cases of
250,000 and 300,000 occur per year in the United States.
[0006] As patients age and/or exhibit habits that increase their
risk of heart disease, certain heart ailments appear suddenly,
while others develop slowly over a period of time. In the cases
where it seems as if the heart ailment has suddenly appeared (e.g.,
SCD), it is often the case that cardiac episodes have previously
occurred, yet, due to the absence of noticeable pain, have gone
undetected. For example, an estimated half of the 3-4 million
Americans that suffer from heart attacks per year, suffer from
"silent" infarctions that are not felt by the patients. In any
event, individuals that experience traumatic cardiac events tend to
have suffered from a series of preceding cardiac difficulties that
occurred over an extended period of time.
[0007] A certain degree of damage results with each detrimental
episode that the heart undergoes. This damage may manifest itself
through altering the cardiac structure, altering the contractile
function of the heart, and/or damaging the heart's electrical
system. When a patient exhibits damage to the electrical system of
the heart in particular, severe issues may arise without the
patient's detection. For example, in about 30% of chronic heart
failure patients, the disease process compromises the myocardium's
ability to contract, which thereby alters the conduction pathways
through the heart. This conduction disturbance can cause a delay in
the beginning of right or left ventricular systole and thereby
induce asynchronous atrial and ventricular activation. Atrial
fibrillation and malignant ventricular arrhythmia are two examples
of such arrhythmias that may result from cardiac disease, both of
which often prove deadly. Atrial fibrillation in particular is one
of the most commonly encountered arrhythmias, and it is correlated
with increased mortality and morbidity due to thromboembolic
complications, especially with respect to undetected asymptomatic
atrial fibrillation. Furthermore, alterations in ventricular
contractility and ventricular volume are frequently followed by
cardiac decompensation, leading to severe symptoms and the
necessity for immediate hospitalization.
[0008] While arrhythmias are detectable on an electrocardiogram
("ECG") and are often treatable, as previously noted, the patient
may be wholly unaware of the occurrence. If left untreated over
time, in some patients an arrhythmia can lead to clinical
instability and an increased risk of death. Accordingly, it is
common for patients with chronic heart failure or other similar
cardiac diseases to exhibit minimal or no symptoms, followed
by--what appears at least to the patient to be--a sudden, drastic
cardiac event that either requires immediate hospitalization or
results in death.
[0009] In patients at increased risk for cardiac difficulties, such
as those patients with chronic heart failure, continuous monitoring
of cardiovascular data is critical. For example, in patients with
chronic heart failure, right ventricle hemodynamic monitoring, left
ventricle wall motion, and ECGs each provide important clinical
information with a favorable impact on outcome. However,
conventional monitoring devices are typically bulky and not
conducive to daily activities. As previously mentioned, one common
monitoring system for monitoring a patient's cardiovascular data is
an ECG. An ECG records electrical signals from the heart via a
series of electrodes attached to the patient's chest. Typically ECG
equipment is large and cumbersome, and is not suitable for a
patient to use after release from the hospital. Further, ECG
results are not easy to decipher and are typically reviewed by a
healthcare practitioner who is qualified to translate the
results.
[0010] Another type of monitoring system is a Holter monitor, or an
ambulatory electrocardiography device. The Holter monitor comprises
a portable memory device for recording cardiovascular data
collected through multiple ECG leads attached to the patient's
chest. The memory device can be worn on a belt or in a case on a
strap worn across the patient's chest. Due to the size of the leads
and the Holter monitor's required placement, it is recommended that
individuals wearing the Holter device wear layers or bulky clothes
to disclose the ECG leads attached to their chest. In addition,
because of the requisite placement of the leads, individuals who
desire to wear the Holter device discretely must wear shirts with a
high neck so as to disclose the entirety of the electrodes.
[0011] Typically, the Holter monitor is applied to the patient for
only 24 hours. Accordingly, the patient must report back to the
physician's office periodically to return the equipment and deliver
the memory device. Thereafter, the information collected must be
reviewed, and the signals inspected to determine if any
cardiovascular abnormality occurred within the previous 24
hours.
[0012] Accordingly, monitoring devices capable of continuously
monitoring the cardiovascular data of a patient are cumbersome due
to the nature of conventional monitoring equipment. Due to the
growing number of patients exhibiting cardiac disorders, there is a
need for a technique and system that allows for early detection and
long term, unburdensome monitoring of heart related disorders.
Furthermore, such novel techniques and equipment should be easy to
understand and implement, universally adoptable, and have
competitive advantages over conventional heart monitoring devices,
such as ECGs and Holter monitors.
BRIEF SUMMARY
[0013] Various embodiments disclosed herein relate to systems and
devices of a portable monitoring system that is capable of
providing continuous, remote monitoring of a heart. Further,
various embodiments disclosed relate to methods for delivering
sensors to the epicardial surface of a heart such that continuous,
remote observation of the heart function can be achieved. For
example, using certain embodiments, a sensor may be delivered to a
specifically targeted area of the external wall of the heart (i.e.
"targeted tissue"). Certain other embodiments provide for access to
the tissue on the external surface of the heart by delivering a
device to the pericardial space using a non-surgical, percutaneous
route that is both rapid and safe.
[0014] At least some of the embodiments disclosed herein include a
system for monitoring the physiologic cardiovascular data of a
heart from the epicardial surface. Such system comprises a sensory
lead, a connecting wire and a memory device. The sensory lead is
coupled with the memory device through the connecting wire and
comprises a connection assembly and at least one sensor for
collecting physiologic data from a targeted tissue. In certain
embodiments, the connection assembly may be configured to traverse
and/or seal an opening in the wall of the heart. In one embodiment,
the system also includes a memory device positioned subcutaneously
on the patient that is capable of transmitting the data received
from the sensors to a remote location, such as a computer or
processor. For example and without limitation, the memory device
may send the data wirelessly, through telemetry or the internet.
Further, the memory device is programmable such that it can process
the data received from the sensory lead.
[0015] In various embodiments, the sensors of the sensory lead have
an attachment mechanism. The attachment mechanisms function to
facilitate the secure and stable attachment of the sensors to the
surface of the heart. The attachment mechanism may comprise a
pinching mechanism, an adhesive mechanism, a suction mechanism, or
any combination thereof. In one embodiment, the attachment
mechanism comprises a scaffold assembly having a body, a first
delivery channel and a plurality of openings. The sensor is coupled
with the body of the scaffold assembly. In this embodiment, the
attachment mechanism further comprises a delivery catheter having a
proximal end, a distal end, and first and second lumens extended
between the proximal end and the distal end. Further, the first
lumen comprises a second delivery channel that is in fluid
communication with the first delivery channel of the scaffold
assembly. The second lumen comprises a wire channel for encasing
the connecting wire of the sensor. This attachment mechanism
facilitates the attachment of the sensor to the epicardial surface
of a heart by delivering an adhesive through the delivery channel
of the delivery catheter, which is advanced to the delivery channel
of the scaffold assembly and released around the sensor through the
plurality of openings in the scaffold assembly. In this manner, an
adhesive is employed to facilitate a secure connection between the
epicardial surface of a heart and the sensor.
[0016] Also disclosed are other embodiments of an attachment
mechanism. In this embodiment, the attachment mechanism comprises a
single-chambered capsula comprising a flexible exterior wall having
an open end, a closed end and an interior. A disk is disposed
within the closed end of the capsula and is releasably coupled with
a sensor such that the sensor extends into the interior of the
capsula. A vacuum catheter is coupled with the exterior wall of the
capsula and is in communication with the interior thereof. When
this embodiment of the attachment mechanism is applied to the
surface of the heart, a vacuum is created within the interior of
the capsula, which shifts the capsula from an upright position to a
collapsed position. In so doing, the sensor is inserted into the
wall of the heart. Thereafter, the sensor is released from the disk
and the remainder of the attachment mechanism is withdrawn from the
body, leaving the sensor securely in place.
[0017] Certain embodiments of the attachment mechanism further
comprise a double-chambered capsula comprising an exterior wall, an
open end, a closed end, and an interior space. A flexible membrane
is disposed across the interior space of the capsula, thereby
defining an upper chamber and a lower chamber. A vacuum catheter is
coupled with the exterior wall of the capsula and in communication
with the lower chamber. A delivery catheter is coupled with the
exterior wall of the capsula and in communication with the upper
chamber. The disk is coupled with the flexible membrane, and at
least one sensor is releasably coupled with the disk such that the
sensor extends into the lower chamber. The open end of the capsula
is configured to removably attach to a targeted tissue such that
the application of suction to the vacuum catheter is capable of
forming a reversible seal with the targeted tissue, and the
flexible membrane is capable of shifting from a first upright
position to a second collapsed position when a gas is introduced
into the upper chamber through the delivery catheter and suction is
applied through the catheter.
[0018] At least one embodiment of the disclosed monitoring systems
may be delivered to the patient's heart through operation of
catheterization and a percutaneous procedure. A system is provided
comprising an engagement catheter having a proximal end, a distal
end and a first and second lumen extending between the proximal and
distal ends; a first delivery catheter comprising a proximal end, a
distal end, and a hollow tube extending between the proximal end
and the distal end. Further the first delivery catheter is
configured for insertion into the second lumen of the engagement
catheter. A needle is also provided at the distal end of the first
delivery catheter and a vacuum port is located at the proximal end
of the engagement catheter. A second delivery catheter is also
provided and is comprised similarly to the first delivery catheter,
except that the second delivery catheter does not comprise a
needle. Embodiments of this system may be used to deliver
embodiments of the monitoring system to a heart.
[0019] Certain other embodiments include the steps of extending
into a blood vessel an elongated hollow tube having a proximal end,
a distal end, and at least one lumen, such that the distal end of
the tube is in contact with the interior wall of the heart;
aspirating the targeted tissue on the interior wall of the heart
such that the wall of the heart is retracted away from a
pericardial sac surrounding the heart to enlarge a pericardial
space between the pericardial sac and the wall of the heart;
delivering a first catheter comprising a needle through the
interior of the elongated tube and puncturing the interior wall of
the heart with the needle; accessing the pericardial space through
the puncture; inserting a second catheter containing the monitoring
system to be implanted and delivering components of the monitoring
system into the pericardial space; and removing the elongated tube
from the body. In at least some embodiments, when the needle is
withdrawn after puncture, the distal end of a guide wire is
inserted through the lumen of the catheter and into the pericardial
space prior to inserting the second catheter into the pericardial
space. Such embodiments may further include the steps of attaching
the memory device of the monitoring system subcutaneously on the
body.
BRIEF DESCRIPTION OF THE DRAWINGS
[0020] FIG. 1A shows a front view of at least one embodiment of an
implantable monitoring device for attachment to on an epicardial
surface;
[0021] FIG. 1B shows a perspective view of one embodiment of a
connection assembly of the monitoring device of FIG. 1A;
[0022] FIG. 2 shows a schematic view of at least one embodiment of
an implantable monitoring device for attachment to an epicardial
surface;
[0023] FIG. 3 shows a front view of at least one embodiment of an
implantable monitoring device for attachment to on an epicardial
surface;
[0024] FIG. 4A shows a bottom view of at least one embodiment of a
sensor of an implantable monitoring system having an attachment
mechanism coupled therewith;
[0025] FIG. 4B shows a cross-sectional view of the delivery
catheter of the attachment mechanism of FIG. 4A along line A-A;
[0026] FIG. 4C shows a cross-sectional view of the attachment
mechanism of FIG. 4A coupled with an epicardial surface of a
heart;
[0027] FIG. 5A shows a perspective view of at least one embodiment
a sensor of an implantable monitoring system having an attachment
mechanism coupled therewith;
[0028] FIG. 5B shows a perspective view of the sensor of FIG. 5A
wherein the attachment mechanism is partially collapsed;
[0029] FIG. 5C shows a perspective view of the sensor of FIG. 5A
wherein the attachment mechanism is fully collapsed;
[0030] FIG. 6A shows a perspective view of at least one embodiment
a sensor of an implantable monitoring system having an attachment
mechanism coupled therewith;
[0031] FIG. 6B shows a perspective view of the sensor of FIG. 5A
wherein the flexible membrane of the attachment mechanism is fully
collapsed;
[0032] FIG. 7 shows a perspective view of at least one embodiment a
sensor of an implantable monitoring system having an attachment
mechanism coupled therewith;
[0033] FIG. 8A shows a perspective view of at least one embodiment
of an engagement catheter and a delivery catheter;
[0034] FIG. 8B shows a percutaneous intravascular pericardial
delivery using at least one embodiment of an engagement catheter
and another embodiment of a delivery catheter;
[0035] FIG. 9A shows a percutaneous intravascular technique for
accessing the pericardial space through a right atrial wall or
atrial appendage using the engagement and delivery catheters shown
in FIG. 8A;
[0036] FIG. 9B shows the embodiment of the engagement catheter
shown in FIG. 9A;
[0037] FIG. 9C shows another view of the distal end of the
engagement catheter embodiment shown in FIGS. 9A and 9B;
[0038] FIG. 10A shows at least one embodiment of an engagement
catheter;
[0039] FIG. 10B shows a cross-sectional view of the proximal end of
the engagement catheter of FIG. 10A;
[0040] FIG. 10C shows a cross-sectional view of the distal end of
the engagement catheter of FIG. 10A;
[0041] FIG. 10D shows the engagement catheter of FIG. 10A
approaching a heart wall from the inside of the heart;
[0042] FIG. 11A shows at least one embodiment of a delivery
catheter;
[0043] FIG. 11B shows a close-up view of the needle shown in FIG.
11A; and
[0044] FIG. 11C shows a cross-sectional view of the needle shown in
FIGS. 11A and 11B.
DETAILED DESCRIPTION
[0045] Reference will now be made to the embodiments illustrated in
the drawings and specific language will be used to describe the
same. It will nevertheless be understood that no limitation of
scope of the appended claims is intended by the description of
these embodiments. For example, while at least one of the
embodiments described herein is described with respect to the
heart, such embodiments may also be applied to other organs of a
body, including, without limitation, the lungs, stomach, and
gastrointestinal tract.
[0046] The disclosed embodiments include devices, systems and
methods useful for remotely monitoring a patient's physiologic data
and overall health. Further, at least one embodiment of the
devices, systems and methods disclosed provides for the noninvasive
and stable application of sensors to the surface of a heart such
that continuous physiologic monitoring may be achieved. By allowing
for continuous observation of a patient's cardiovascular data over
a long term basis, a physician can 1) monitor the long-term
characteristics of cardiovascular parameters; 2) observe
alterations in hemodynamic parameters that take place during
significant clinical events; and 3) explore the utility of long
term hemodynamic information in changing the treatment management
and reduction in hospitalizations. Further, the embodiments
disclosed herein do not require that the patient be confined in the
hospital. As such, the patient can return to his or her daily
routines all while enjoying a reduced level of stress and related
anxiety with respect to his or her condition, as he or she may be
comforted by the fact they are being continuously monitored.
[0047] FIG. 1A shows at least one embodiment of a monitoring system
100 for monitoring cardiovascular physiologic data. The monitoring
system 100 comprises a sensory lead 102, a memory device 104, and a
first connecting wire 108. In this embodiment, the first connecting
wire 108 is coupled with both the sensory lead 102 and the memory
device 104 such that the sensory lead 102 and the memory device 104
can exchange data and electrical energy between one another.
Briefly, in one embodiment, when the monitoring system 100 is
positioned within the patient, the sensory lead 102 is inserted
through catheterization and transcutaneous puncture into the
pericardial space proximate to the surface of the heart 10.
Further, the connecting wire 108 coupled with the connection
assembly 105 of the sensory lead 102 extends from the interior of
the heart 10 to the memory device 104 that is implanted
subcutaneously.
[0048] In the at least one embodiment of the monitoring system 100
shown in FIG. 1A, the memory device 104 is any device capable of
receiving, storing, and transmitting data. In at least one
embodiment, the memory device 104 is configured to transmit data to
a remote location using telemetry, the internet, or any other means
of wireless transmission. Further, the memory device 104 may also
be capable of performing programmed operations on data stored
therein. For example, the memory device 104 may process and
organize received data prior to transmitting such data to a remote
location. In the at least one embodiment shown in FIG. 1A, the
memory device 104 is inserted subcutaneously on the patient. For
example, the memory device 104 may be positioned subcutaneously
beneath the right or left clavicle of the patient. In this manner,
the memory device 104 may be accessed in a manner minimally
invasive to the patient.
[0049] As previously described, the memory device 104 is coupled
with the sensory lead 102 through the first connecting wire 108.
The first connecting wire 108 comprises a proximate end and a
distal end and may be any conduit through which a data signal
and/or electrical energy may be transferred from the sensory lead
102 to the memory device 104. The proximate end of the connecting
wire 108 is coupled with the memory device 104. When the memory
device 104 is inserted subcutaneously, the first connecting wire
108 extends through either the jugular or femoral vein and the
superior or inferior vena cava, respectively, in a fashion similar
to the insertion of a pacemaker unit (e.g., catheterization).
Within the interior of the heart 10, the distal end of the first
connecting wire 108 couples with the connection assembly 105 of the
sensory lead 102.
[0050] In FIG. 1B, details of the sensory lead 102 are shown.
Generally, the sensory lead 102 comprises any device that is
capable of collecting physiologic data from the epicardial surface
of a heart 10. In one embodiment, the sensory lead 102 includes a
connection assembly 105 and a sensor 106 coupled together by a
second connecting wire 109. As the connection assembly 105 is also
coupled with the memory device 104 through the first connecting
wire 108, the connection assembly 105 of the sensory lead 102
enables the transfer of data and electrical energy between the
sensor 106 and the memory device 104. The connection can be located
over the epicardial surface or at the level of the atrial wall
puncture (at the entrance of the epicardial sac). The size of the
catheter can include a sealing system for example, a biodegradable
adhesive material (fibrin glue, cianometacrilate, etc.). The plug
may be made from any suitable material, including casein,
polyurethane, silicone, and polytetrafluoroethylene.
[0051] The connection assembly 105 of the sensory lead 102
specifically comprises a first end 120, a second end 122, and a
body 124. The first end 120 of the connection assembly 105 is
coupled with the connecting wire 108 and the second end 122 of the
connection assembly 105 is coupled with the second connecting wire
109. In the embodiments shown in FIGS. 1A and 1B, the body 124 of
the connection assembly 105 is configured to traverse an opening in
the wall of the heart 10. In one embodiment, the opening may be in
the atrial wall. In another embodiment, the opening may be in the
atrial appendage. In yet another embodiment, the body 124 of the
connection assembly 105 is configured to substantially plug the
opening through which it is applied, thereby preventing any leaks
from within the heart 10 into the pericardial sac. In this
embodiment, the connection assembly 105 may be comprised of any
suitable material, including without limitation, casein,
polyurethane, silicone, and/or polytetrafluoroethylene.
[0052] Although the connection assembly 105 has been described as
traversing the wall of the heart 10 with respect to this
embodiment, the connection assembly 105 of the sensory lead 102 may
be positioned in any location within the body of the patient,
provided that the placement of the connection assembly 105 allows
for the connection assembly 105 to adequately function as a conduit
between the memory device 104/first connecting wire 108 and the
sensory lead 102. For example, in at least one embodiment, the
connection assembly 105 is positioned on the epicardial surface of
the heart 10. In this embodiment, after the connection assembly 105
is delivered to the surface of the heart 10 through an opening, a
delivery catheter is used to seal the opening in the wall of the
heart 10 (as described in more detail below).
[0053] As previously described, the sensor 106 is in communication
with the connection assembly 105 through the second connecting wire
109. The sensor 106 is configured to attach to the epicardial
surface of the heart 10 and is capable of obtaining physiologic
cardiovascular data therefrom. For example, the sensor 106 may be
employed to collect hemodynamic data, pressure data, data regarding
depolarization and repolarization, or any other type of data that
is collectable through a sensor. The sensor 106 may comprise
microtransducers, piezo crystals, pressure sensors, or any other
device capable of obtaining data from a tissue or organ when the
sensor 106 is coupled therewith. In at least one embodiment, the
sensor 106 receives power from the memory device 104 through the
first connecting wire 108. As the memory device 104 may be
positioned subcutaneously, the power supply for the sensor 106 may
be easily and noninvasively recharged or replaced without accessing
the epicardial surface.
[0054] In at least one embodiment, the sensor 106 further comprises
a mechanism to facilitate the secure attachment of the sensor 106
to a target epicardial surface. In this embodiment, the attachment
mechanism may comprise a pinching mechanism, an adhesive mechanism,
a penetrating mechanism, or any other mechanism capable of
facilitating the secure attachment of the sensor 106 to the target
epicardial surface (described in more detail with respect to FIGS.
5-7B). Through the use of the attachment mechanism, the sensor 106
may be securely anchored in position on the target tissue.
Accordingly, the use of the attachment mechanism in conjunction
with the sensor 106 decreases the risk that the inherent movement
of the functioning heart will detrimentally affect the quality or
amount of data collected by the sensor 106.
[0055] Now referring to FIG. 2, a schematic representation of at
least one embodiment of the monitoring system 100 is shown. In this
embodiment, the monitoring system 100 further comprises a remote
processor 110. The remote processor 110 comprises any processing
means known in the art, including without limitation, a server,
remote computer, or remote handheld device, provided the processing
means is capable of receiving data transmitted by the memory device
104. In one embodiment, the remote processor 110 further comprises
a display device such that a user at a remote location can view the
data collected by the sensor 106.
[0056] In operation, the monitoring system 100 functions to collect
data from the surface of the heart 10 and to either store such
collected data in the memory device 104 or transmit such
information to a remote location, such as the remote processor 110.
Specifically, the sensor 106 obtains information from the
epicardial tissue to which the sensor 106 is attached. The
collected data is transferred through the second connecting wire
109, the connection assembly 105, and the first connecting wire 108
to the memory device 104. The memory device 104 receives the
collected data and either stores the collected data for a period of
time, or immediately transmits the collected data to the remote
processor 110 via a wireless connection. In one embodiment, the
memory device 104 is programmed to transmit the collected data
intermittently to the remote processor 110 at preset intervals. In
an alternative embodiment, the memory device 104 is programmed to
transmit the collected data to the remote processor 110 in a
continuous stream.
[0057] When the data is received by the remote processor 110, a
clinician can monitor the collected data from a remote location. In
this manner, a patient may reside in the comfort of his or her own
home, yet be continuously monitored for an impending or severe
cardiovascular event. In addition, the data collected by the
monitoring system 100 can provide guidance in selecting and/or
modifying the medical therapy that the patient is receiving.
[0058] In at least one alternative embodiment, the memory device
104 may be programmed to process the collected data prior to
transmitting the data to the remote processor 110. Accordingly,
after the memory device 104 receives the collected data from the
sensory lead 102, the memory device 104 performs preprogrammed
operations on the collected data to reduce the need for processing
the data at the remote processor 110. For example, and without
limitation, the memory device 104 may be programmed to organize and
interpret the data prior to transmission. In this at least one
embodiment, the remote processor 110 need not be capable of
performing processing functions and can merely be used to display
the processed data. This may be particularly useful if a clinician
wishes to receive the collected data on a device that does not
necessarily support complex data processing programs, such as a
handheld device.
[0059] Now referring to FIG. 3, an alternative embodiment of the
monitoring system 100 is shown. A monitoring system 200 comprises
components identical to those of monitoring system 100 of FIGS. 1A
and 1B, except that the sensory lead 202 of the monitoring system
200 comprises multiple sensors: a first sensor 204, a second sensor
206, a third sensor 208, and a fourth sensor 210. In this
embodiment, each of the four sensors 204, 206, 208, 210 is coupled
with an independent connecting wire 214, 216, 218, 220,
respectively. Further, each of the connecting wires 214, 216, 218,
220 is coupled with the connection assembly 105 such that the data
collected from each of the sensors 204, 206, 208, 210 is
transferred through the connection assembly 105, the first
connecting wire 108, and to the subcutaneous memory device 104.
Although the sensory lead 202 shown in FIG. 3 comprises four
sensors 204, 206, 208, 210, the sensory lead 202 may include any
number of sensors.
[0060] The sensors may be positioned at various locations on the
epicardial surface of the heart 10 in order to obtain the desired
data. FIG. 3 shows the sensors 204, 206, 208, 210 strategically
positioned to collect specific data from different locations of the
heart 10 in order to detect complications. For example, in FIG. 3
each of the sensors 204, 206, 208, 210 are positioned on the heart
10 to monitor the following data: the sensor 204 is positioned to
collect electrogram data (e.g. heart rate, arterial fibrillation,
and/or premature ventricular contraction data), the sensor 206 is
positioned to monitor coronary flow-velocity, the sensor 208 is
positioned to monitor left ventricular wall motion (i.e. to
determine wall thickness, segmental shortening, etc.), and the
sensor 210 is positioned to monitor the right ventricle hemodynamic
outflow. Although these positions are referenced herein by way of
example, the sensors 204, 206, 208, 210 may be positioned on any
area of the epicardial surface of the heart 10.
[0061] Referring back to the sensors 106, 204, 206, 208, 210 of the
above described monitoring systems 100, 200, several embodiments of
the attachment mechanism of the sensor 106 are described. While the
singular term "the sensor 106" is used herein in describing several
embodiments, it will be recognized that any type or number of
sensors may be employed.
[0062] As previously indicated, one embodiment of the sensor 106
may comprises a mechanism to facilitate the secure attachment of
the sensor 106 to the target epicardial surface. Now referring to
FIG. 4A, a bottom view of one embodiment of a sensor 106 having an
attachment mechanism 415 is shown. The attachment mechanism 415
comprises an adhesive mechanism and functions to secure a sensor
106 to the epicardial surface of the heart 10 using an
adhesive.
[0063] In this embodiment, the attachment mechanism 415 comprises a
delivery catheter 418 coupled with a scaffold assembly 428. The
scaffold assembly 428 comprises a body having a top portion and a
bottom portion. Additionally, in one embodiment, the body of the
scaffold assembly 428 further comprises a plurality of magnetic
beads 430 or biologic glue embedded therein. The sensor 106 is
embedded within the bottom portion of the scaffold assembly 428.
The body of the scaffold assembly 428 can be configured in any
shape or size, provided the scaffold system 428 surrounds the
perimeter of the sensor 106. For example, and without limitation,
the body of the scaffold assembly 428 shown in FIG. 4A is
configured in a circular shape and the sensor 106 is disposed in
the center of the bottom portion of the ferromagnetic scaffold
assembly 428 such that at least a portion of the sensor 106 is
exposed to contact the tissue (see FIG. 4C). Additionally, in the
embodiment shown in FIG. 4A, the plurality of magnetic beads 430 or
biologic glue surrounds the sensor 106.
[0064] In at least one embodiment, the scaffold assembly 428
further comprises a delivery channel 432 that extends around its
periphery. The scaffold assembly 428 also has a number of openings
that are in fluid communication with the delivery channel 432 and
can be used to transmit fluid or a viscous material from the
delivery channel 432 to a tissue in close proximity to the
attachment mechanism 415.
[0065] In yet another embodiment, the scaffold assembly 428
exhibits a degree of flexibility and thus the attachment mechanism
415 can be moved between a first folded position (not shown) and a
second open position (see FIGS. 4A and 4B). When the attachment
mechanism 415 is in the first folded position, the attachment
mechanism 415 is rolled up in such a fashion that the folded
scaffold assembly 428 and the sensor 106 embedded therein can be
easily advanced through a lumen or a catheter. However, when the
attachment mechanism 415 is extended to the second open position,
the ferromagnetic scaffold system 428 comprises a flat, open
structure capable of affixing to a substantially flat or irregular
surface. Further, when the scaffold assembly 428 is positioned in
the second open position, at least a portion of the sensor 106 is
exposed and capable of coupling with a targeted tissue.
[0066] Referring back to FIG. 4A, the attachment mechanism 415 is
coupled with the distal end of the delivery catheter 418. Although
the delivery catheter 418 comprises a proximal end and a distal
end, FIG. 4A shows only the distal end. The delivery catheter 418
comprises a conduit having two concentric lumens: a delivery
channel 420 and a wire channel 422. In this at least one
embodiment, the delivery channel 420 is positioned around the
exterior of the wire channel 422 such that the wire channel 422 is
completely encased within the delivery channel 420. Further, the
delivery channel 420 and the wire channel 422 are not in
communication with one another.
[0067] The delivery channel 420 of the delivery catheter 418 is
used to deliver adhesive to the scaffold assembly 428. As shown in
FIG. 4B, the delivery channel 420 is ring-shaped, which tends to
provide relatively even movement of the adhesive through the
channel, but other shapes of delivery channels may be suitable. The
distal end of the delivery channel 420 is in fluid communication
with the delivery channel 432 of the scaffold assembly 428. In this
manner, adhesive introduced into the delivery channel 420 of the
delivery catheter 418 can be advanced into the delivery channel 432
of the attachment mechanism 415 and expelled onto the target tissue
through the number of openings in the ferromagnetic scaffold
assembly 428. In the event a magnetic adhesive is employed, the
plurality of magnetic beads 430 embedded within the scaffold
assembly 428 facilitate a secure connection with the magnetic
adhesive by coupling therewith.
[0068] The wire channel 422 is used to facilitate communication
between the sensor 106 and the memory device 104 (not shown). The
wire channel 422 houses the second connecting wire 109 of the
sensory lead 102. As previously described in connection with FIG.
1A, the second connecting wire 109 of the sensory lead 102 couples
with both the sensor 106 and the connection assembly 105 (not
shown).
[0069] In operation, the attachment assembly 415 and the sensor 106
are delivered concurrently to the pericardial space under direct
camera laser Doppler probe, radioscopic or echocardiographic
guidance. After the epicardial surface of the heart 10 is accessed,
and the attachment mechanism 415 and the sensor 106 are delivered
to the proximate location of the targeted epicardial surface. In
one embodiment, the attachment mechanism 415 is positioned in the
first folded position as it is guided toward the desired location
on the epicardial surface of the heart 10. When the attachment
mechanism 415 and the sensor 106 are positioned proximate to the
desired location, a user introduces an adhesive into the delivery
channel 420 of the delivery catheter 418, which can then be
advanced through the channel 420 via pressure. For example, a user
may squeeze an external portion of the delivery catheter 418,
thereby forcing the adhesive to advance into the delivery channel
432 and through the number of openings within the scaffold assembly
428 surrounding the sensor 106. In the event the attachment
mechanism 415 is introduced into the pericardial space in the first
folded position, the scaffold assembly 428 necessarily moves into
the second open position as the adhesive is delivered through the
openings in the ferromagnetic scaffold assembly 428.
[0070] As the adhesive flows through the number of openings in the
ferromagnetic scaffold assembly 428, the sensor 106 is moved into
contact with the targeted epicardial surface. In one embodiment,
the sensor 106 and the surface of the heart 10 may be 45.degree. in
order to maximize the receiving and transmission ability of the
sensor 106. When the sensor 106 is coupled with the heart 10, the
adhesive flowing through the openings in the scaffold assembly 428
is sandwiched between the epicardial surface surrounding the sensor
106 and the scaffold assembly 428. In this manner, the scaffold
assembly 428 and the sensor 106 are flatly bound to the epicardial
surface of the heart 10.
[0071] This embodiment of the attachment mechanism 415 provides
stability for the sensor 106 by preventing the sensor 106 from
becoming dislodged from the surface of the heart 10. While this
embodiment employs an adhesive, such as a biological,
non-biological, or magnetic glue, to adhere the sensor 106 to the
surface of the heart 10, various other mechanisms of attachment may
be provided to achieve the same results.
[0072] Now referring to FIG. 5A, a perspective view of another
embodiment of an attachment mechanism 515 is shown. Similar to the
attachment mechanism 415, the attachment mechanism 515 may be used
in conjunction with the sensory leads and sensors described herein,
or with any similar sensory system for which it is beneficial to
enable secure attachment to a targeted tissue.
[0073] The attachment mechanism 515 functions to secure a sensor
106 to the epicardial surface of the heart 10 using suction. In
this embodiment, the attachment mechanism 515 comprises a vacuum
catheter 518 coupled with a capsula 520. Further, the attachment
mechanism 515 is particularly efficient if the sensor 106 comprises
an arrow or anchor-like shape.
[0074] In this at least one embodiment, the attachment mechanism
515 comprises a single-chambered capsula 520 coupled with a vacuum
catheter 518. As shown in FIG. 5A, the capsula 520 is dish-shaped
and comprises an open end a closed end, and an interior chamber;
however, other shapes of capsulas may be suitable. The majority of
the capsula 520 is formed of a semi-flexible or flexible material;
however, a hard plastic center 522 is disposed proximate to the
midpoint of the capsula 520. The sensor 106 is removably coupled
with the hard plastic center 522 such that the sensor 106 protrudes
into the interior chamber of the capsula 520 as shown in FIGS. 5A
and 5B. Similar to the embodiments shown in FIGS. 1A and 3, the
second connecting wire 109 is coupled with the sensor 106 directly
such that the sensor 106 is in communication with the connection
assembly 502.
[0075] Referring back to FIG. 5A, the vacuum catheter 518 of the
attachment mechanism 515 comprises any tubular conduit that is
capable of providing suction. Although the vacuum catheter 518
comprises a proximal end and a distal end, FIGS. 5A, 5B, and 5C
only illustrate the distal end of the vacuum catheter 518. The
distal end of the vacuum catheter 518 is coupled with the capsula
520 such that the vacuum catheter 518 is in communication with the
interior chamber of the capsula 520. In this manner, when a vacuum
source is applied to the proximal end of the vacuum catheter 518,
suction is provided within the interior chamber of the capsula
520.
[0076] The vacuum catheter 518 is used to provide suction such that
the capsula 520 can precisely and stably bind to a targeted tissue.
In one embodiment, a syringe is attached to the proximal end of the
vacuum catheter 518 to provide appropriate suction through the
vacuum catheter 518, and thereby within the interior chamber of the
capsula 520. In addition, other types of vacuum sources may be
used, such as a controlled vacuum system providing specific suction
pressures.
[0077] Now referring to FIGS. 5B and 5C, the operation of the
attachment mechanism 515 is described. When the attachment
mechanism 515 and the sensor 106 are positioned proximate to the
targeted epicardial surface of the heart 10, suction is provided to
the interior chamber of the capsula 520 through the vacuum catheter
518. By way of the suctional force, the capsula 520 is coupled with
the targeted epicardial surface on the heart 10. Accordingly, the
suction forms a releasable seal between the capsula 520 and the
epicardial surface.
[0078] Due to the flexible properties of the capsula 520, the force
of the suction causes the capsula 520 to collapse or flatten onto
the targeted epicardial surface, thereby pulling the hard plastic
center 522 and the sensor 106 downward. When enough force is
applied, the sensor 106 punctures the epicardial surface and is
embedded within the targeted tissue. In this manner, the collapsing
capsula 520 enables the insertion of the sensor 106 into the
surface of the heart 10 via a pressurized introduction. Further,
the clinician using the attachment mechanism 515 to deliver the
sensor 106 can use the hard plastic center 522 as a guide for the
placement of the sensor 106 on the heart 10. In one embodiment, an
adhesive may further be applied to the sensor 106 such that the
sensor 106 is retained in the heart 10 by insertion and
adhesion.
[0079] After the sensor 106 is sufficiently embedded within the
epicardial surface, the sensor 106 is released from the hard
plastic center 522 and the capsula 520 is withdrawn. The
configuration of the sensor 106 in an anchor or arrow-like shape
facilitates retention of the sensor 106 within the epicardial
tissue such that retraction is prevented. Accordingly, this
embodiment of the attachment mechanism 515 functions to 1) locate
and attach to the targeted epicardial surface; and 2) safely and
accurately insert the sensor 106 into the cardiac tissue.
[0080] In at least one alternative embodiment of the attachment
mechanism 515, the sensor 106 comprises a blunt shape so as not to
facilitate insertion into the surface of the heart 10. In this
embodiment, when the capsula 520 is collapsed and the sensor 106 is
placed in contact with the surface of the heart 10, an adhesive is
employed to achieve the secure placement of the sensor 106.
Accordingly, an adhesive can be used in conjunction with suction to
achieve the stable placement of the sensor 106.
[0081] Referring now to FIGS. 6A and 6B, an alternative embodiment
of an attachment mechanism 615 is shown. The attachment mechanism
615 functions to secure the sensor 106 to the epicardial surface of
the heart 10 using pressure and suction. Similar to the attachment
mechanism 515, the attachment mechanism 615 comprises a capsula 620
having a hard plastic center 622, a sensor 106, the second
connecting wire 109, and a vacuum catheter 618. This embodiment of
the attachment mechanism 615 is particularly efficient if the
sensor 106 comprises an arrow or anchor-like configuration. Unlike
the capsula 520 of FIGS. 5A-5C, the capsula 620 of FIGS. 6A and 6B
comprises two interior chambers and a delivery catheter 624. The
attachment mechanism 615 can be used in conjunction with the
sensory leads 102, 202 and the sensors 106, 206 described herein,
or with any similar sensory system for which it is beneficial to
ensure a sensory is securely attached to a targeted tissue.
[0082] In the at least one embodiment shown in FIG. 6A, the
attachment mechanism 615 comprises a double-chambered capsula 620
coupled with a vacuum catheter 618 and a delivery catheter 624.
Specifically, the capsula 620 in FIG. 6A is dish-shaped and
comprises an open end, a closed end, and an interior. Further, the
capsula 620 comprises a membrane 634 extending through the interior
of the capsula 620, thereby defining an upper chamber 630 and a
lower chamber 632. The upper chamber 630 is a closed chamber,
enclosed by the walls of the capsula 620 and the membrane 634.
Alternatively, the lower chamber 632 is open, with the membrane 634
forming the only boundary thereof.
[0083] The membrane 634 defining the upper and lower chambers 630,
632 is formed of a semi-flexible or flexible material. The hard
plastic center 622 is disposed through the membrane 634 in a
location proximal to the midpoint of the capsula 620. Similar to
attachment mechanism 515, the sensor 106 is removably coupled with
the hard plastic center 622 such that the sensor 106 protrudes into
the interior of the lower chamber 632 of the capsula 620 as shown
in FIG. 6A. Similar to the embodiments shown in FIGS. 1A and 3, the
second connecting wire 109 is coupled with the sensor 106 and
extends to the exterior of the capsula 620 through the open end of
the lower chamber 632.
[0084] The vacuum catheter 618 of the attachment mechanism 615
comprises any tubular conduit that is capable of providing suction.
Although the vacuum catheter 618 comprises a proximal end and a
distal end, FIGS. 6A and 6B only illustrate the distal end of the
vacuum catheter 618. The distal end of the vacuum catheter 618 is
coupled with the capsula 620 such that the vacuum catheter 618 is
in communication with the lower chamber 632 of the capsula 620. In
this manner, when a vacuum source is applied to the proximal end of
the vacuum catheter 618, suction is provided within the lower
chamber 632 of the capsula 620.
[0085] The delivery catheter 624 of the attachment mechanism 615
comprises any tubular conduit that is capable of delivering a gas
to the upper chamber 630 of the capsula 620. Although the delivery
catheter 624 comprises a proximal end and a distal end, FIGS. 6A
and 6B only illustrate the distal end of the delivery catheter 624.
The distal end of the delivery catheter 624 is coupled with the
capsula 620 such that the delivery catheter 624 is in communication
with the upper chamber 630. Accordingly, the upper chamber 630 of
the capsula 620 can be filled with a gas introduced through the
proximal end of the delivery catheter 624. Further, due to the
flexible characteristics of the membrane 634, the upper chamber 630
undergoes a downward expansion when a sufficient amount of gas is
introduced therein. In this manner, as the upper chamber 630 fills
with gas, the pressure within the upper chamber 630 creates a
downward force on the membrane 634, thereby reducing the size of
the lower chamber 632 and pushing the hard plastic center 622 and
sensor 610 downward (see FIG. 6B).
[0086] In operation, the attachment mechanism 615 and the sensor
106 are positioned proximate to the targeted epicardial surface of
the heart 10. Thereafter, a syringe or other means for providing
suction is attached to the proximal end of the vacuum catheter 618
to provide appropriate suction therethrough. In this manner, a
vacuum is created within the lower chamber 632 that is capable of
suctioning the capsula 620 onto the targeted epicardial surface and
forming a seal therewith.
[0087] After the capsula 620 is coupled with the epicardial surface
through suction, a gas is introduced into the proximal end of the
delivery catheter 624, and thereby the upper chamber 632 that is in
communication therewith. In one embodiment, carbon dioxide gas may
be used. The addition of gas to the upper chamber 630 increases the
pressure within the upper chamber 632, thereby asserting a downward
pressure on the membrane 624. The flexible nature of the membrane
624, the vacuum conditions within the lower chamber 632, and the
increasing pressure in the upper chamber 630 all facilitate the
expansion of the membrane 624 downward and the collapse of the
lower chamber 632 (see FIG. 6B). As the lower chamber 632 collapses
onto the epicardial surface, the hard plastic center 622 and the
sensor 106 are pulled down into the same. In the embodiment where
the sensor 106 comprises an arrow-like or anchor-like shape, the
sensor 106 punctures the epicardial surface and is embedded within
the targeted tissue.
[0088] After the sensor 106 is sufficiently embedded within the
epicardial surface, suction through the vacuum catheter 618 and
injection of gas through the delivery catheter 624 are ceased and
the sensor 106 is released from the hard plastic center 622. The
attachment mechanism 615 is thereafter withdrawn from the patient,
leaving the sensor 106 embedded in the targeted epicardial
tissue.
[0089] In an alternative embodiment, the sensor 106 may be
configured in an adhesive spherical design as shown in FIG. 7, for
use in conjunction with the attachment mechanism 615. In this
embodiment, an adhesive, including, without limitation, a
biological glue, is applied to the surface of the sensor 106 such
that the adhesive is employed in addition to the suction and gas
injection to facilitate the secure attachment of the sensor 106 to
the epicardial surface.
[0090] The various embodiments of the monitoring system 100
disclosed herein are inserted into a patient using the systems,
devices and methods disclosed in the co-pending International
Patent Application No. PCT/US2007/015207, the totality of which is
incorporated herein by reference. FIG. 8A shows one embodiment of a
catheter system 800 for providing percutaneous, intravascular
access to the pericardial space through an atrial wall or the wall
of the atrial appendage.
[0091] Unlike the relatively stiff pericardial sac, the atrial wall
and atrial appendage are rather soft and deformable. Hence, suction
of the atrial wall or atrial appendage can provide significantly
more clearance of the cardiac structure from the pericardium as
compared to suction of the pericardium. Furthermore, navigation
from the intravascular region (inside of the heart) provides more
certainty of position of vital cardiac structures than does
intrathoracic access (outside of the heart). Through accessing the
pericardial space, sensors may be delivered via the pericardial
space and positioned in directly contact with the exterior wall of
the heart without opening the chest cavity of the patient.
[0092] In the embodiment of the catheter system shown in FIG. 8A,
the catheter system 800 includes an engagement catheter 820, a
delivery catheter 830, and a needle 840. Although each of the
engagement catheter 820, the delivery catheter 830, and the needle
840 comprise a proximal end and a distal end, FIG. 8A shows only
the distal end. The engagement catheter 820 has a lumen through
which the delivery catheter 830 has been inserted, and the delivery
catheter 830 has a lumen through which the needle 840 has been
inserted. The delivery catheter 830 also has a number of openings
850 that can be used to transmit fluid from the lumen of the
catheter to the heart tissue in close proximity to the distal end
of the catheter.
[0093] As shown in more detail in FIGS. 9A, 9B, and 9C the
engagement catheter 820 includes a vacuum channel 860 used for
suction of a targeted tissue 865 in the heart and an injection
channel 870 used for infusion of substances to the targeted tissue
865, including, for example and without limitation, a biological or
non-biological degradable adhesive. As shown in FIGS. 9B and 9C,
the injection channel 870 is ring-shaped, which tends to provide
relatively even dispersal of the infused substance over the
targeted tissue, but other shapes of injection channels may be
suitable. A syringe 880 is attached to injection channel 870 for
delivery of the appropriate substances to the injection channel
870, and a syringe 880 is attached to the vacuum channel 860
through a vacuum port (not shown) at the proximal end of the
engagement catheter 820 to provide appropriate suction through
vacuum channel 860. At the distal end of the engagement catheter
820, a suction port 895 is attached to the vacuum channel 860 for
contacting targeted tissue 865, such that suction port 895
surrounds targeted tissue 865, which is thereby encompassed within
the circumference of suction port 895. Although the syringe 890 is
shown in FIG. 9B as the vacuum source providing suction for the
engagement catheter 820, other types of vacuum sources may be used,
such as a controlled vacuum system providing specific suction
pressures. Similarly, the syringe 880 serves as the external fluid
source in the embodiment shown in FIG. 9B, but other external fluid
sources may be used.
[0094] A route of entry for use of various embodiments disclosed
herein is through the jugular or femoral vein to the superior or
inferior vena cava, respectively, to the right atrial wall or
atrial appendage (percutaneously) to the pericardial sac (through
puncture).
[0095] Referring now to FIG. 8B, an engagement catheter 800 is
placed via standard approach the jugular or femoral vein. The
catheter 800, which may be 4 or 5 Fr., is positioned under
fluoroscopic or echocardiographic guidance into the right atrial
appendage 810. Suction is initiated to aspirate a portion of the
atrial appendage 810 away from the pericardial sac that surrounds
the heart. As explained herein, aspiration of the heart tissue is
evidenced when no blood can be pulled back through the engagement
catheter 800 and, if suction pressure is being measured, when the
suction pressure gradually increases. A small perforation is made
in the aspirated atrial appendage 810 with a needle such as needle
840, as shown in FIGS. 8A and 9A. A guide wire (not shown) can then
be advanced through the delivery catheter 830 into the pericardial
space to secure the point of entry 825 through the atrial appendage
810 and to guide further insertion of the delivery catheter 830 or
another catheter. Fluoroscopy or echocardiogram can be used to
confirm the position of the catheter in the pericardial space.
Alternatively, a pressure tip needle can sense the pressure and
measure the pressure change from the atrium (about 10 mmHg) to the
pericardial space (about 2 mmHg).
[0096] Although aspiration of the atrial wall or the atrial
appendage retracts the wall or appendage from the pericardial sac
to create additional pericardial space, carbon dioxide gas can be
delivered through a catheter, such as the delivery catheter 830,
into the pericardial space to create additional space between the
pericardial sac and the heart surface. FIGS. 10A, 10B, 10C, and 10D
show another embodiment of an engagement catheter as disclosed
herein. The engagement catheter 900 is an elongated tube having a
proximal end 910 and a distal end 920, as well as two lumens 930,
940 extending between proximal end 910 and distal end 920. The
lumens 930, 940 are formed by the concentric inner wall 950 and
outer wall 960, as particularly shown in FIGS. 10B and 10C. At the
proximal end 910, the engagement catheter 900 includes a vacuum
port 970, which is attached to the lumen 930 so that a vacuum
source can be attached to the vacuum port 970 to create suction in
the lumen 930, thereby forming a suction channel. At the distal end
920 of the catheter 900, a suction port 980 is attached to the
lumen 930 so that the suction port 980 can be placed in contact
with the heart tissue 975 (see FIG. 10D) for aspirating the tissue,
thereby forming a vacuum seal between the suction port 980 and the
tissue 975 when the vacuum source is attached and engaged. The
vacuum seal enables the suction port 980 to grip, stabilize, and
retract the tissue 975. For example, attaching a suction port to an
interior atrial wall using a vacuum source enables the suction port
to retract the atrial wall from the pericardial sac surrounding the
heart, which enlarges the pericardial space between the atrial wall
and the pericardial sac.
[0097] As shown in FIG. 10C, two internal lumen supports 1010, 1020
are located within the lumen 930 and are attached to the inner wall
950 and the outer wall 960 to provide support to the walls. These
lumen supports divide the lumen 930 into two suction channels.
Although the internal lumen supports 1010, 1020 extend from the
distal end 920 of the catheter 900 along a substantial portion of
the length of the catheter 900, the internal lumen supports 910,
920 may or may not span the entire length of the catheter 900.
Indeed, as shown in FIGS. 10A, 10B, and 10C, the internal lumen
supports 1010, 1020 do not extend to the proximal end 910 to ensure
that the suction from the external vacuum source is distributed
relatively evenly around the circumference of the catheter 900.
Although the embodiment shown in FIG. 10C includes two internal
lumen supports, other embodiments may have just one internal
support or even three or more such supports.
[0098] FIG. 10D shows the engagement catheter 900 approaching the
heart tissue 975 for attachment thereto. It is important for the
clinician performing the procedure to know when the suction port
has engaged the tissue of the atrial wall or the atrial appendage.
For example, in reference to FIG. 10D, it is clear that the suction
port 980 has not fully engaged the tissue 975 such that a seal is
formed. However, because the suction port 980 is not usually seen
during the procedure, the clinician may determine when the proper
vacuum seal between the atrial tissue and the suction port has been
made by monitoring the amount of blood that is aspirated, by
monitoring the suction pressure with a pressure sensor/regulator,
or both. For example, as the engagement catheter 900 approaches the
atrial wall tissue (such as tissue 975) and is approximately in
position, the suction can be activated through the lumen 930. A
certain level of suction (e.g., about 10 mmHg) can be imposed and
measured with a pressure sensor/regulator. As long as the catheter
900 does not engage the wall, some blood will be aspirated into the
catheter and the suction pressure will remain the same. However,
when the catheter 900 engages or attaches to the wall of the heart
(depicted as the tissue 975 in FIG. 10D), minimal blood is
aspirated and the suction pressure will start to gradually
increase. Each of these signs can alert the clinician (through
alarm or other means) as an indication of engagement. The pressure
regulator is then able to maintain the suction pressure at a preset
value to prevent over-suction of the tissue.
[0099] Referring now to FIGS. 11A, 11B, and 11C, there is shown a
delivery catheter 1050 comprising an elongated hollow tube 1080
having a proximal end 1060, a distal end 1070, and a lumen 1085
along the length of the catheter. Extending from the distal end
1070 is a hollow needle 1090 in communication with the lumen 1085.
The needle 1090 is attached to the distal end 1070 in the
embodiment of FIGS. 11A, 11B, and 11C, but, in other embodiments,
the needle may be removably attached to, or otherwise located at,
the distal end of the catheter (see FIG. 8A). In the embodiment
shown in FIGS. 11A, 11B, and 11C, as in certain other embodiments
having an attached needle, the junction (i.e., site of attachment)
between the hollow tube 1080 and the needle 1090 forms a security
notch 1110 circumferentially around the needle 1090 to prevent the
needle 1090 from over-perforation. Thus, when a clinician inserts
the needle 1090 through an atrial wall to gain access to the
pericardial space, the clinician will not, under normal conditions,
unintentionally perforate the pericardial sac with the needle 1090
because the larger diameter of the hollow tube 1080 (as compared to
that of the needle 1090) at the security notch 1110 hinders further
needle insertion. Although the security notch 1110 is formed by the
junction of the hollow tube 1080 and the needle 1090 in the
embodiment shown in FIGS. 11A, 11B, and 11C, other embodiments may
have a security notch that is configured differently. For example,
a security notch may include a band, ring, or similar device that
is attached to the needle a suitable distance from the tip of the
needle. Like the security notch 1110, other security notch
embodiments hinder insertion of the needle past the notch itself by
presenting a larger profile than the profile of the needle such
that the notch does not easily enter the hole in the tissue caused
by entry of the needle.
[0100] It is useful for the clinician performing the procedure to
know when the needle has punctured the atrial tissue. This can be
done in several ways. For example, the delivery catheter can be
connected to a pressure transducer to measure pressure at the tip
of the needle. Because the pressure is lower and much less
pulsatile in the pericardial space than in the atrium, the
clinician can recognize immediately when the needle passes through
the atrial tissue into the pericardial space.
[0101] Alternatively, as shown in FIG. 11B, the needle 1090 may be
connected to a strain gauge 1115 as part of the catheter assembly.
When the needle 1090 contacts tissue (not shown), the needle 1090
will be deformed. The deformation will be transmitted to the strain
gauge 1115 and an electrical signal will reflect the deformation
(through a classical wheatstone bridge), thereby alerting the
clinician. Such confirmation of the puncture of the wall can
prevent over-puncture and can provide additional control of the
procedure.
[0102] In some embodiments, a delivery catheter, such as the
catheter 1050 shown in FIGS. 11A, 11B, and 11C, is used with an
engagement catheter, such as the catheter 900 shown in FIGS. 10A,
10B, 10C, and 10D, to gain access to the pericardial space between
the heart wall and the pericardial sac. For example, the engagement
catheter 900 may be inserted into the vascular system and advanced
such that the distal end of the engagement catheter is within the
atrium. The engagement catheter may be attached to the targeted
tissue on the interior of a wall of the atrium using a suction port
as disclosed herein. A standard guide wire may be inserted through
the lumen of the delivery catheter as the delivery catheter is
inserted through the inner lumen of the engagement catheter, such
as the lumen 940 shown in FIGS. 10B and 10C. Use of the guide wire
enables more effective navigation of the delivery catheter 1050 and
prevents the needle 1090 from damaging the inner wall 950 of the
engagement catheter 900. When the tip of the delivery catheter with
the protruding guide wire reaches the atrium, the wire is pulled
back, and the needle is pushed forward to perforate the targeted
tissue. The guide wire is then advanced through the perforation
into the pericardial space, providing access to the pericardial
space through the atrial wall.
[0103] In one embodiment, a delivery catheter, such as the delivery
catheter 1050, may be configured to deliver components of a
monitoring system 100, 200 to the pericardial sac. For example, the
lumen 1085 of the delivery catheter 1050 may be used for delivering
the sensory lead 102 into the pericardial space after the needle
1090 is inserted through the atrial wall or the atrial appendage.
In this embodiment, after the needle 1090 is inserted through the
atrial wall or the atrial appendage, the delivery catheter 1050 to
which the needle 1090 is attached is withdrawn from inner lumen of
the engagement catheter. Thereafter, a second delivery catheter
configured to deliver components of the monitoring system 100 is
inserted through the inner lumen of the engagement catheter and
advanced into the pericardial space. After the distal end of the
second delivery catheter is positioned in the pericardial space,
the at least one sensor 106 of the sensory lead 102 is delivered
such that the sensor 106 is positioned adjacent to a targeted
epicardial surface of the heart 10. The sensor 106 is then attached
to the epicardial surface pursuant to the methods previously
described herein.
[0104] After the sensors 106 are securely coupled with the
epicardial surface of the heart 10, the delivery catheter 1050 is
withdrawn slightly, allowing the second connecting wire 109 to
extend therefrom. When the distal end of the delivery catheter 1050
is positioned within the interior of the heart proximate to the
puncture in the heart wall, the connection assembly 105 is inserted
into the puncture with the first end 120 positioned within the
interior of the heart 10 and the second end 122 positioned within
the epicardial space (see FIG. 1B). In this manner, the puncture is
sealed and a conduit is provided through which the data collected
from the surface of the heart 10 by the sensors 102 can be
transferred to the memory device 104 positioned subcutaneously.
[0105] After the connection assembly 105 is secured, the delivery
catheter 1050 is withdrawn through the inner lumen of the
engagement catheter. As the delivery catheter 1050 is withdrawn,
the first connecting wire 108 is allowed to remain in the inner
lumen of the engagement catheter. In this manner, when the
engagement catheter is withdrawn from the blood vessel, the first
connecting wire 108 remains within the blood vessel (similar to the
placement of pacemaker leads), thereby maintaining communication
with the sensory lead 105 positioned on the heart 10 and the memory
device 104. The memory device 104 may be implanted subcutaneously
in any location on the body, so long as a connection is maintained
with the first connecting wire 108.
[0106] When it is desirable to have the connection assembly 105
positioned adjacent to the epicardial surface of the heart 10 (as
opposed to secured within an opening in the wall of the heart 10),
the delivery catheter 1050 can be operated to seal the puncture in
the wall of the heart 10, thereby preventing any leakage into the
pericardial sac. In this embodiment, the delivery catheter 1050
further comprises a sealing system (not shown) configured to seal
the puncture in the wall of the heart 10 after the sensory lead 102
is delivered to the epicardial surface thereof. In one embodiment,
the sealing system may employ a biodegradable adhesive material,
such as fibrin glue or cianometacrilate, to effectively seal the
puncture.
[0107] The various embodiments disclosed herein may be used by
clinicians, for example and among other things: (1) to perform
transeptal puncture and delivery of a catheter through the left
atrial appendage for electrophysiological therapy, biopsy, etc.;
(2) to deliver and place epicardial, right atrial, and right and
left ventricle pacing leads; and (3) to visualize the pericardial
space with endo-camera, scope, or laser Doppler probe to navigate
the epicardial surface of the heart for therapeutic delivery,
diagnosis, lead placement, mapping, etc. Many other applications,
not explicitly listed here, are also possible and within the scope
of the present disclosure.
[0108] While various embodiments of devices, systems, and methods
for accessing the heart tissue have been described in considerable
detail herein, the embodiments are merely offered by way of
non-limiting examples of the invention described herein. Many
variations and modifications of the embodiments described herein
will be apparent to one of ordinary skill in the art in light of
this disclosure. It will therefore be understood by those skilled
in the art that various changes and modifications may be made, and
equivalents may be substituted for elements thereof, without
departing from the scope of the invention. Indeed, this disclosure
is not intended to be exhaustive or to limit the scope of the
invention. The scope of the invention is to be defined by the
appended claims, and by their equivalents.
[0109] Further, in describing representative embodiments, the
disclosure may have presented a method and/or process as a
particular sequence of steps. However, to the extent that the
method or process does not rely on the particular order of steps
set forth herein, the method or process should not be limited to
the particular sequence of steps described. As one of ordinary
skill in the art would appreciate, other sequences of steps may be
possible. Therefore, the particular order of the steps disclosed
herein should not be construed as limitations on the claims. In
addition, the claims directed to a method and/or process should not
be limited to the performance of their steps in the order written,
and one skilled in the art can readily appreciate that the
sequences may be varied and still remain within the spirit and
scope of the present invention.
[0110] It is therefore intended that the invention will include,
and this description and the appended claims will encompass, all
modifications and changes apparent to those of ordinary skill in
the art based on this disclosure.
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